Improvement in automatic grain-weighing scales



h PETERS, PHOYOMTHOGRAFMER, WASHINGTON. n c,

UNrreD STATES PATENT' Ormea.

HENRY FAIIIBANKS, OF ST. JOHNSBURY, VERMONT.

IMPROVEMENT IN AUTOMATIC GRAIN-WEIGHING SCALES.

Specification forming part of Letters Patent No. 92,436, dated .Iuly 13,1869.

To all fwhom it may concern:

Be it known thatI, HENRY FAIRBANKS, of St. Johnsbury, in the county ofCaledonia, in the Stale of Vermont, have invented certain new and usefulImprovements in Scales for Veighing Grain, applicable also to theweighing of analogous material; and I do hereby declare that thefollowing isa full and exact description thereof.

I will first describe what I consider the best means of carrying out myinvention, and will afterward designate the poilus which Ibi-lieve to benew therein.

The accompanying drawings form a part of this specification.

Figure I is a side elevation, partly in section, showing the scaleheamand the provisions for changing at each oscillation of the latter theposition of the spout which leads the grain into the separate bin. Fig.2 isa corresponding end view. Fig. 3 is a plan view of the same parts,with the cover or boxing ot the delicate parts removed. In these guresthe weighingebeam is in its lowest position. Fig. 4 is a sectioncorresponding to Fig. 1, but with the beam in its highest-position. Fig.5 is a crosssection, showing the parts in the position assumed in Fig.4. Fig. Gis a perspective view of the entire machine on a smaller scale.

Similar letters of reference indicate corresponding parts in all thetigures.

The drawings represent the novel parts with so much of the ordinaryparts as seems necesary to indicate their relations thereto.

The parts not represented may be made in any approved manner.

I prefer the severalmodifications 0f the form ordinarily adopted in ourmanufacture, and known as the Fairbanks patent scales.7

A is a rigid frame-work, which supports the several parts, and A is abox, made of wood or other suitable material, removable at will, thefunctionof which is simply to cover and protect the several parts fromaccident and derangement.

B is thescalebcam, graduated as usual, and carrying a movable poise, b,which may, it desired, be rigidly set at any desired point by the aid ofa set-screw or other ordinary device. The several knife-edges on thisbcam,thehang 'er or support A2, bolted upon the frame A, the

connections W to the loaded platform below, and the provisions forattaching a permanent weight at the other end of the beam to balance theplatform will be readily understood without explanation.

I will describe minutely only the parts in which the novelty lies.

The armB extends upward from near the end of the lever B, and carries across-pin, b',- playiug freely up and down through a hole in theframe-work A as the beam B is tilted in one direction or the other. Along and slender spring, C, presses upward against this pin b', andmoves up and down therewith, as rep resented. The spring C is riveted orotherwise secured to the other side of the lever D, which turns inbearings d on the upper side of the frame-work A. This lever has anotch, as represented, at the point d', adapted to receive a sharpcorner or an glecar'ried upon the upper end of the arm E, which will bedescribed farther on. The lever D extends over the pin b', so that asthe scale-beam B rises it lifts the lever D by means ofthe pin b. Thearm E is carried on a cross-shaft or axis, e, which is supported inbearings a little above the framework A. This shaft e carries also twoother arms7 with which it is connected, (marked respectively E and E2.)The shaft e and its connected arms rock or oscillate at each operationof weighing, and the arms E and E2`a're alternately depressed throughliberal openings provided in the frame-work A, as represented. The arm Eextends under the crosspiu b', and is depressed thereby at proper times.The arm E2 carries a weight, E3, the gravity of which is sufficient tocause the shaft e and its attachments to turn with considerable force.

M' and M2, Fig. 6, are two spacious compartments or bins, into one orthe other of which the grain is constantly received and is alteruatelydischarged. The discharging operation is sudden and by ordinarymeaus,.which need not be described. The receiving is more gradual, thegrain being received in a stream of moderate size through the movablespout N. The grain is supplied into this spout from above through anordinary spout, which is in line, or nearly in line,with the.supporting-shaft A sufficient force not only to overcome the slighttension of the spring C, but a'so to act against the arm E' withsutiieient force to tilt the shaft e and its appurtenances, and toelevate the weight E3 until the corner or angle at the top of the arm Eenters the notch fl in the lever D. The parts remain in this conditionuntil, by the accumulation of the grain in the bin, the beam B israised. The force of the spring .C assists the lever B in commencing torise and until it comes into the position for weighing correctly. Itgradually diminishes its force in lifting the beam B, and at the sametime .loses the force with which it correspondingly depresses the leverD, to which it is bolted,

. until the bin having been tilled to the proper weight, the beam Bleaves the spring C entirely and, rising higher, touches the under sideof the notched lever D. |The notch d' and the corresponding corner orangular piece carried on the arm E, which enters this notch, areaccurately shaped and smooth, sothat the lever D, having been relievedfrom the depressing force of the spring C, is lifted by a very slighttouch against its under surface.' This slight touch it receives from thecross-pin b',

and instantly the lever D is thrownup and the arm E released. The shafte and its attachments are now turned with considerable force by thegravity of the Weight E3. The turning of this shaft and its attachmentseffects the required change of position of the dischargingspout N,turning it first in one direction to empty it into one bin and then inthe other direction to empty it into the other bin. The turning of thisdischarging-spout in the opposite directions is effected alternately byprecisely similar motions of the beam B and its connections, and of thelever. D, and of the shaft e and its connections. At one ascent of thebeam B it liberates the arm E, andthe descent ofthe weight E3 shifts thespout Nin one direction, and at the next ascent of the beam B theposition of the spout N is shifted in the opposite direction. The meansof effecting this is as' follows: v

To the arm E is connected a rod, G, which extends along nearly to theshaft a and is forked, as represented. (See the plan view, Fig. 3.) Across-bar, G', extending across be tween the forked arms rides on acentral fix! ture or ridge, A3, which is so formed and arrangedrelatively to the fork G and the cross bar G' that as. the latter ismoved horizontally with considerable violence by the sudden descent ofthe weight E3 it rests during the first part of its motion on the plainupper surface of the frame-work A, but during the middle or latterportion of its motion it is lifted by the central fixture, A3. Now theforked piece G is free to tilt on this central piece, A3. In otherwords, it can allow either end of the fork to remain down and allow theother end to rise up at pleasure. Either end of the arms or forks g' g3is adapted to catch hold of and operate a corresponding` arm, n' n3,fixed on the upright shaft n. These arms n' n2, being in fact parts ofasingle straight cross-bar fixed on the upright shaft u, and runningclose to the upper surface of the frame-Work A, are alternately caughtand turned by the fork g' g2. There are pins or stops A4 A5, whichprevent the arms n' n2 from turningfarther than is desired. At eachthrust of the piece G one of the forks g' g2 catches the correspondingarm, n' n3. So soon as it is firmly engaged therewith, so that it cannotrise, the incline plane, which I have termed the central fixture, A3,"tries to lift the entire forked piece, but not heing able to do this byreason'of the engagementofone fork, it tilts the forked piece, liftingthe other fork-arm, so. that it is of no effect. This construction andcombination is peculiar and may deserve minute description. Supposingthe parts to be in the position represented in strong lines in Fig. 3,the descentof the weight E3, and the corresponding vigorous lthrust ofthe forked piece g' g3, results, first, in

the engagement of the arm or fork g' with the arm n; next, in suddenlyturning the upright shaft a and the attached grain-spout.N into theposition indicated in dottedred lines, it havingpreviously been in theposition shown in dotted black lines, and meantime in the tilting of theforked piece g' g2 by reason of the riding up of the attachedeross-barG' upon the incline A3, so that the other arm, g2, has no eect on thearm n2, but vpasses idly over it. Now, on the return of the forked pieceg' g2 with its attached cross-bar G', and the repetition of the thrust,the other arm, g2, first engages, and af ter ,it has got hold of andlocked under the corresponding arm, u2, the lifting of the forked pieceat the center by means of the incline A3 now tilts the forked piece g"g3 to the opposite side, so that the arm g' is nowr lifted and passesidly over without engaging with the arm n'.

It will be seen that the ends of the forks g' g2 are adapted to not onlystrike againstthe arms a' a2, but to hook under them, so as toeffectually resist any tendency to disengage by I lifting.

The means above described are sufficient for changing the position ofthe spout N and its attachments, but they fail to provide against theforce of the current of grain, or any other cause which might in theinterim disturb the position ofthe parts. To guard against any suchaccdent I have provided the springcatches H H2, which are secured on afixed cross-piece, A, and are adapted to receive the ends of the arms u'n2 in notches h' h2. The arms n' or n2 next to be operated upon is heldin the corresponding noteh,.lt' or h2, with considerable force,sufficient to resist any slight tendency of the parts to change theirpositions. At each thrust ofthe forked piece G and its attachments thearm on which it aets is not only caught by the proper forked piece, butis detached or liberated from the catch. The liberation of the arm isnot effected antecedent to thc engaging of the fork therewith, but thewhole operation is nearly7 instantaneous. In short, at each thrust ot'the rod G one of the arms of the forked piece g g2 (in the positionshown in Fig. 3) first engages with the corresponding spring-catch, H',and detiects it ontward so as to release the arm n'. It next turns theconnected grainspont N'until the arm it' is quite over against the stopA4, and the other arm, n2, is in its proper position for the nextoperation, and is held by the corresponding spring-catch, H2. Afterhaving thus performed all that is required for its complete operation,it returns bythe descent of the scalebeam B and the turning of the shafte and its connections, and remains quiescent until its bin is full andthe notched lever D is again the notched lever 'D, and to depress therocking lever E' and its connections at eachweighing operation,substantially as and for thepnrposes herein set forth.

2. The weighted lever E E' E2 and the connected weight or constant forceE3, arranged to be set by the depression of the beam B, to beheld by thelever-D, and ultimately released by the rising ofthe beam B, and to turnforcibly on such release, substantially as and for the purposes hereinset forth.

3. The spring C, arranged as rf presented, and adapted to carry up thescale-beam to the position for weighing correctly, and also to hold downthe notched lever D with a force graduated n accordance with the amountot' depression ofthe scale-beam, as and for the purpose described.

4. The thrusting-piece G g'gZ, with its crossbar G', or its equivalent,constructed and arranged as represented, and adapted to operaterelatively to the arms n' n2, which operate the grain-spout N,substantially in the manner and for the purpose herein set forth.

5. The combination and the arrangement of the thrusting part g' g2,deecting or tilting ridge A3, arms-nn2 with the notched lever D d',rocking lever E E' E2, and scale-beam B b', all adapted for jointoperation substantially in the manner and with the ettect herein setforth.

6. The spring-catches H h' H2 h2, arranged relatively to the arms n' n2and to the forks g' g2, substantially as and for the' purposes hereinset forth.

In testimony whereof I have hereunto set my name in presence of twosubscribing wit;-

nesses.

HENRY FAIRBANKS. Witnesses:

A. N. FAIRBANKS, RUTLEY B. PAGE.

